Process for machining gears and machine for performing the same

Abstract

Shaving machine in which a motor controlling the cutting feed is coupled to a work-table which can move relative to the frame. The cutting feed motor is a direct current motor and the control device of this motor comprises several circuits for energizing the motor corresponding to at least two and preferably three different speeds of the motor in one rotation direction, and at least one speed in the other rotation direction. A special application of the invention is to the shaving of gears.

What is claimed is: 
     
       1. A continuous process for machining gears to final predetermined dimensions in a shaving machine including means for supporting a shaving tool and means for supporting the gear to be shaved by performing a continuous shaving process comprising the steps of performing a first step of moving at least one of said supporting members towards the other in a single continuous movement to a predetermined position at which the spacing therebetween theoretically corresponds to that required to obtain the desired final predetermined dimension of the gear by shaving with said tool; immediately thereafter performing a withdrawal step of moving said at least one supporting member slightly away from the other supporting member to relieve stresses in the shaving machine and gear built up during said first step; and immediately thereafter performing a finishing step of moving said at least one supporting member towards the other supporting member to said predetermined position. 
     
     
       2. A process as defined in claim 1 wherein said first step comprises moving said at least one supporting member towards the other supporting member in three successive stages including the steps of moving said at least one supporting member at a first relatively high speed in a first movement stage towards said predetermined position; then moving said at least one supporting member at a slower speed, closer to said predetermined position, in a second, roughing stage, and then moving said at least one supporting member at a third speed, slower than said second speed, in a first stage to said predetermined position. 
     
     
       3. A process as defined in claim 2 wherein said withdrawal step is performed after said step of moving said at least one supporting member at a third speed and comprises moving said at least one support member in an opposite direction away from said predetermined position at a relatively rapid speed; and said finishing step comprises moving said at least one support member back towards said predetermined position at a slow speed at least equal to said third speed. 
     
     
       4. A process as defined in claim 3 including a final step performed after said finishing step comprising moving said at least one support member away from said predetermined position at a relatively rapid speed to a position wherein said supporting means are spaced for loading. 
     
     
       5. A process as defined in claim 1 including the step of controlling said at least one support means to move said at least one support means rapidly away from said predetermined position to a position wherein the supporting means are spaced for loading at any stage of the process.